7.5" Block of Promicroceras Ammonites - Polished Side & Prepped Side
One face of this specimen has been polished, while the opposite side has been left rough with dozens of observable, complete ammonites. The base of the rock has been cut flat for presentation purposes.
Ammonites were predatory mollusks that resembled a squid with a shell. These cephalopods had eyes, tentacles, and spiral shells. They are more closely related to a living octopus, though the shells resemble that of a nautilus. Ammonites appeared in the fossil record about 240 million years ago and they barely survived several major extinction events. The last lineages disappeared 65 million years ago at the end of the Cretaceous.